CVE-2024-56565

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to drop all discards after creating snapshot on lvm device Piergiorgio reported a bug in bugzilla as below: ------------[ cut here ]------------ WARNING: CPU: 2 PID: 969 at fs/f2fs/segment.c:1330 RIP: 0010:__submit_discard_cmd+0x27d/0x400 [f2fs] Call Trace: __issue_discard_cmd+0x1ca/0x350 [f2fs] issue_discard_thread+0x191/0x480 [f2fs] kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 w/ below testcase, it can reproduce this bug quickly: - pvcreate /dev/vdb - vgcreate myvg1 /dev/vdb - lvcreate -L 1024m -n mylv1 myvg1 - mount /dev/myvg1/mylv1 /mnt/f2fs - dd if=/dev/zero of=/mnt/f2fs/file bs=1M count=20 - sync - rm /mnt/f2fs/file - sync - lvcreate -L 1024m -s -n mylv1-snapshot /dev/myvg1/mylv1 - umount /mnt/f2fs The root cause is: it will update discard_max_bytes of mounted lvm device to zero after creating snapshot on this lvm device, then, __submit_discard_cmd() will pass parameter @nr_sects w/ zero value to __blkdev_issue_discard(), it returns a NULL bio pointer, result in panic. This patch changes as below for fixing: 1. Let's drop all remained discards in f2fs_unfreeze() if snapshot of lvm device is created. 2. Checking discard_max_bytes before submitting discard during __submit_discard_cmd().

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/15136c3861a3341db261ebdbb6ae4ae1765635e2	Patch
https://git.kernel.org/stable/c/bc8aeb04fd80cb8cfae3058445c84410fd0beb5e	Patch
https://git.kernel.org/stable/c/ed24ab98242f8d22b66fbe0452c97751b5ea4e22	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::

History

No history.

Information

Published : 2024-12-27 15:15

Updated : 2025-10-07 18:34

NVD link : CVE-2024-56565

Mitre link : CVE-2024-56565

CVE.ORG link : CVE-2024-56565

JSON object : View

Products Affected

linux

linux_kernel

CWE

NVD-CWE-noinfo

{"id": "CVE-2024-56565", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2024-12-27T15:15:15.400", "references": [{"url": "https://git.kernel.org/stable/c/15136c3861a3341db261ebdbb6ae4ae1765635e2", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/bc8aeb04fd80cb8cfae3058445c84410fd0beb5e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/ed24ab98242f8d22b66fbe0452c97751b5ea4e22", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix to drop all discards after creating snapshot on lvm device\n\nPiergiorgio reported a bug in bugzilla as below:\n\n------------[ cut here ]------------\nWARNING: CPU: 2 PID: 969 at fs/f2fs/segment.c:1330\nRIP: 0010:__submit_discard_cmd+0x27d/0x400 [f2fs]\nCall Trace:\n __issue_discard_cmd+0x1ca/0x350 [f2fs]\n issue_discard_thread+0x191/0x480 [f2fs]\n kthread+0xcf/0x100\n ret_from_fork+0x31/0x50\n ret_from_fork_asm+0x1a/0x30\n\nw/ below testcase, it can reproduce this bug quickly:\n- pvcreate /dev/vdb\n- vgcreate myvg1 /dev/vdb\n- lvcreate -L 1024m -n mylv1 myvg1\n- mount /dev/myvg1/mylv1 /mnt/f2fs\n- dd if=/dev/zero of=/mnt/f2fs/file bs=1M count=20\n- sync\n- rm /mnt/f2fs/file\n- sync\n- lvcreate -L 1024m -s -n mylv1-snapshot /dev/myvg1/mylv1\n- umount /mnt/f2fs\n\nThe root cause is: it will update discard_max_bytes of mounted lvm\ndevice to zero after creating snapshot on this lvm device, then,\n__submit_discard_cmd() will pass parameter @nr_sects w/ zero value\nto __blkdev_issue_discard(), it returns a NULL bio pointer, result\nin panic.\n\nThis patch changes as below for fixing:\n1. Let's drop all remained discards in f2fs_unfreeze() if snapshot\nof lvm device is created.\n2. Checking discard_max_bytes before submitting discard during\n__submit_discard_cmd()."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: f2fs: correcci\u00f3n para descartar todos los descartes despu\u00e9s de crear una instant\u00e1nea en el dispositivo lvm Piergiorgio inform\u00f3 un error en bugzilla como se muestra a continuaci\u00f3n: ------------[ cortar aqu\u00ed ]------------ ADVERTENCIA: CPU: 2 PID: 969 en fs/f2fs/segment.c:1330 RIP: 0010:__submit_discard_cmd+0x27d/0x400 [f2fs] Seguimiento de llamadas: __issue_discard_cmd+0x1ca/0x350 [f2fs] issue_discard_thread+0x191/0x480 [f2fs] kthread+0xcf/0x100 ret_from_fork+0x31/0x50 ret_from_fork_asm+0x1a/0x30 con el siguiente caso de prueba, puede reproducir este error r\u00e1pidamente: - pvcreate /dev/vdb - vgcreate myvg1 /dev/vdb - lvcreate -L 1024m -n mylv1 myvg1 - mount /dev/myvg1/mylv1 /mnt/f2fs - dd if=/dev/zero of=/mnt/f2fs/file bs=1M count=20 - sync - rm /mnt/f2fs/file - sync - lvcreate -L 1024m -s -n mylv1-snapshot /dev/myvg1/mylv1 - umount /mnt/f2fs La causa ra\u00edz es: actualizar\u00e1 discard_max_bytes del dispositivo lvm montado a cero despu\u00e9s de crear una instant\u00e1nea en este dispositivo lvm, luego, __submit_discard_cmd() pasar\u00e1 el par\u00e1metro @nr_sects con valor cero a __blkdev_issue_discard(), devuelve un puntero bio NULL, resultado En p\u00e1nico. Este parche cambia lo siguiente para solucionar: 1. Descartamos todos los descartes restantes en f2fs_unfreeze() si se crea una instant\u00e1nea del dispositivo lvm. 2. Comprobamos discard_max_bytes antes de enviar el descarte durante __submit_discard_cmd()."}], "lastModified": "2025-10-07T18:34:52.570", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "11F0A5BB-68E6-4E86-921A-80BA2447967F", "versionEndExcluding": "6.6.66", "versionStartIncluding": "4.19"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "04756810-D093-4B43-B1D9-CF5035968061", "versionEndExcluding": "6.12.4", "versionStartIncluding": "6.7"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}